Feltham Community College on the outskirts of west London doesn't appear on a table of the best 100 schools in the country, but in the last four years it has turned its fortunes around. It also has another reason to feel proud – one of its alumni has recently won two Olympic gold medals.

Mo Farah came to the college just over a decade ago and formed an exceptionally strong bond with the place. He met his wife to be at Feltham. Alan Watkinson – the school's PE teacher, who first spotted the future distance running world champion's talent – went on to be Farah's best man. The school specialises in sport and has clearly delivered – there's no doubt that a double gold medal alumnus has had a positive effect on the students. They were more than aware of the connection before the Olympics; Farah's face adorns the walls.

"The story of Mo Farah," says student Amanda Curry who is still smiling from her A*, A, C result, "has always been around. We've always had posters of him just to remind ourselves that it is possible to exceed the reputation of a place and do well."

And Feltham's reputation needed to be overcome. Four years ago, the school was designated as a London Challenge school – in need of extra support – and being threatened with special measures if it didn't turn things around.

But for a school where 31% are on free school meals, the results – 35% A*- B grades and over two thirds at A*–C are an achievement which can not be ascribed to posters alone.

The grades are part of the college's long term trend of improvement and way up on last years results where only 41% of pupils scored A*–C. They even have an in-house prodigy to champion. William Cheung, who is in his final year of GCSEs, took maths A-level two years early and has just come away with an A. Unsuprisingly he is grinning ear-to-ear.

The pupils suggest it is down to the sheer energy of the deputy head, Jay Lockwood, who is in charge of the sixth form. At 28, he came to Feltham after quitting the City, on the Teach First programme which seeks to put the UK's top performing graduates into deprived schools.

"There's so much encouragement from Mr Lockwood as you can see," says Curry as he comes bounding through double doors with a set of students following.

"He's incredibly motivational, he makes people aim higher all the time. No matter where you're from, who you are, he always makes sure people aim higher than expected." And that is especially important she says when you come from an area "where people don't expect the best."

There are a further 30 or so Teach First teachers at Feltham and recently Labour schools minister, Lord Adonis ascribed the programme to helping turning around failing schools in the capital. So this may have been part of the shift in culture of the pupils. As one teaching assistant put it, even the students that do badly in their exams have stopped giving up. Now they ask how can they can improve on what they have.

Lockwood puts the success of his pupils down to a more structured timetable and focusing on punctuality and attendance. When he took charge of the A-level group last year he got rid of the free-wheeling periods between lessons. Instead, along with the student body, the school instituted structured study sessions that kept pupils away from the nearby multiplex cinema and bowling alley, and in the library under supervision.

On the old brick wall at the entrance to the sixth form common room is the word EXCUSES in a circle with a red line painted through it. To emphasise the point Lockwood shows me a metal pin badge with the same "no excuses'' logo. "These are for the students next year, I'm going to get them all to wear one". I ask if the teenagers aren't likely to rebel. He says they'll grumble but they'll put them on.

Fatema Taleb, who was in floods of tears at having achieved two Bs and a C, tells me that Lockwood's new rules were welcomed once the students could see they were working. "To be honest with you, it could be strict sometimes but with his strict rules, we've improved." She is hoping to eventually do a masters degree.

But there appears to be a third ingredient to this dose of aspiration set within the bounds of solid structures and that is the school's social media policy.

The school, Lockwood says, was forever competing for students' attention with Facebook and Twitter. But instead of trying to draw them away, the college now has its own presence on both sites which have become a bit of a hub for school activities and pictures. It is more than simply a virtual noticeboard or broadcast service. "It's our way of trying to up our communication and make it as interactive a sixth form as we possibly can," Lockwood says. Even the English lit department – where students this year scored a whopping 90% rate at A*- B grade – has its own Facebook page.

So what about the future? After the excitement of a gold medal Olympian alumnus and brilliant A-level success? "Well, next year we're hoping to have our first Oxbridge candidates for a number of years," says Lockwood. "That will be very exciting."

Watch the Guardian's video of the students at Mo Farah's former college getting their grades in our video online